



 
Hi Izayah. If y = 2x + 4, then anywhere you see "y", you can write "2x + 4" instead, right? They are equal, after all. Actually, it is always a good idea to use extra parentheses in these cases, so you should use "(2x + 4)". Now, if 3x + y = 7, what do you get when you substitute for (2x + 4) in place of the y? Can you find the value of x? With that, can you find the corresponding value of y? Hope this helps,  


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